CN108569082B

CN108569082B - Wheel mounting structure

Info

Publication number: CN108569082B
Application number: CN201810178901.8A
Authority: CN
Inventors: 中川健治
Original assignee: Toyota Motor Corp
Current assignee: Toyota Motor Corp
Priority date: 2017-03-07
Filing date: 2018-03-05
Publication date: 2021-01-12
Anticipated expiration: 2038-03-05
Also published as: JP6604484B2; JP2018144675A; EP3372422B1; US10744815B2; CN108569082A; EP3372422A1; US20180257425A1

Abstract

A wheel (50) is mounted to a hub (20) having a sleeve portion (23) that has a substantially cylindrical shape and that has a rotation axis (90) as a center axis and that protrudes from a hub shaft portion (21) to a position outside a vehicle body with respect to a flange portion (22). A first cylindrical outer peripheral surface (23b) parallel to the axis of rotation and a groove (23g) adjacent to the first cylindrical outer peripheral surface on the vehicle body outer side are formed in the sleeve portion, and an annular protrusion (54) is provided on the inner peripheral surface (52a) of the center hole (52) so as to protrude toward the wheel hub attachment surface (51a) of the wheel toward the center of the wheel. In a state where the wheel is fixed to the flange portion by using the fastening and connecting member (60), a fitting portion (24) formed on the outer peripheral surface of the first cylinder and the annular protrusion (54) are sleeve-fitted, and in a state where the fastening and connecting member is removed, the annular protrusion is locked in a groove formed in the sleeve portion.

Description

Wheel mounting structure

Technical Field

The present invention relates to a wheel mounting structure for mounting a wheel hub of a vehicle by fitting a wheel sleeve thereto.

Background

Conventionally, a wheel rolling bearing device (hereinafter, also referred to as a "conventional device") having the following structure is known: a wheel is fixed to a hub by providing a plurality of bolts for mounting the wheel on the hub and fastening nuts (hub nuts) to the bolts (see, for example, patent document 1). In contrast, the wheel rolling bearing device having a structure in which a plurality of bolt holes (screw holes) for mounting a wheel are formed in a hub and fastening bolts (hub bolts) are fastened to the bolt holes, thereby fixing the wheel to the hub, has an advantage of being light in weight as compared with conventional devices.

Patent document 1: japanese patent laid-open No. 2012-148643 (FIG. 1)

Disclosure of Invention

Most of the hubs of the above-described devices and wheels mounted on the hubs adopt a sleeve fitting structure for facilitating the alignment of the hubs with each other. The sleeve fitting structure is a structure in which an outer peripheral surface of a cylindrical protrusion protruding from the vehicle outer side of the hub to the vehicle outer side coaxially with the hub abuts against an inner peripheral surface of a hole formed in the center of the wheel. In the sleeve fitting portion having such a structure, the hub and the wheel are easily fixed to each other when corrosion occurs. Therefore, the fitting portion of the hub and the wheel is formed near the front end of the protrusion in the rotation axis direction of the hub, and the length of the fitting portion in the rotation axis direction is made short. This makes it possible to relatively easily detach the wheel from the hub.

However, in the wheel hub of the rolling bearing device for a wheel having a structure in which the wheel hub is fastened and connected by a plurality of hub nuts, when all the hub nuts are removed, even if the fitting of the sleeve fitting portion is loosened, the wheel is supported by the bolt protruding from the wheel hub, and therefore the possibility of the wheel falling is low. However, in this case, the bolts supporting the wheels may be deformed. On the other hand, in a hub of a rolling bearing device for a wheel having a structure in which the hub is fastened and connected by a plurality of hub bolts, when all the hub bolts are removed, only the sleeve fitting portion is provided at a portion supporting the wheel. Therefore, in this case, if the fitting of the sleeve fitting portion is released, the wheel may fall off and be damaged. Further, when the wheel falls off, the wheel may collide with the brake member, and the brake member may be damaged. As a result, the number of steps for wheel replacement may increase. In this way, in a hub having a structure in which a wheel is fixed by fastening a plurality of hub bolts, there is a problem in that the efficiency and reliability of the wheel replacement work may be reduced.

The present invention has been made to solve the above problems. That is, an object of the present invention is to provide a wheel mounting structure capable of preventing a wheel from coming off and/or damage of parts at the time of wheel replacement and improving the work efficiency of wheel replacement in a wheel hub having a structure in which a wheel is fixed by fastening a hub bolt or a hub nut.

The wheel mounting structure of the present invention (hereinafter also referred to as "the present invention structure") is a structure for mounting a wheel (50) to a hub (20) of a vehicle.

The hub includes: a hub shaft portion (21); a flange portion (22) that is a disk-shaped portion extending from the hub shaft portion in parallel with a plane perpendicular to a rotation axis (90) of the hub, and that has a fixing surface (22a) for fixing the wheel using a plurality of fastening connection members (60) on the vehicle body outer side of the vehicle; and a sleeve portion (23) that is a cylindrical portion having the rotation axis as a center axis and that protrudes from the hub shaft portion to the vehicle body outer side of the flange portion.

In the wheel, a center hole (52) through which the sleeve portion can be inserted is formed in the center of the wheel, and a plurality of bolt holes (53) through which the plurality of fastening and connecting members can be inserted are formed around the center hole.

Further, a first cylindrical outer peripheral surface (23b) having the rotation axis as a central axis and a groove (23g) adjacent to the first cylindrical outer peripheral surface on the vehicle body outer side of the first cylindrical outer peripheral surface are formed on the sleeve portion, an annular protrusion (54) protruding toward the center of the wheel is formed on the inner peripheral surface of the center hole on the hub attachment surface (51a) side of the wheel, a fitting portion (24) formed on the first cylindrical outer peripheral surface is sleeve-fitted to the annular protrusion in a state where the wheel is fixed to the flange portion by the plurality of fastening connection members, and the annular protrusion is engaged with the groove in a state where the fixation of the wheel by the plurality of fastening connection members is released.

According to the above configuration, in a state where the wheel is fixed to the flange portion using the plurality of fastening and connecting members, the annular protrusion and the fitting portion function as a "sleeve fitting portion". When the wheel using the plurality of fastening members is released from the fastening, that is, when all the fastening members (hub bolts or hub nuts) are removed, the wheel is supported by the sleeve fitting portion. However, as described above, the sleeve fitting portion is designed to be easily detached, and thus it is difficult to support the wheel only by the supporting force of the sleeve fitting portion. Thus, when all the fastening and connecting members are removed, the wheel falls down and the annular protrusion is disengaged from the fitting portion and locked in the adjacent groove. Thus, the "annular protrusion" and the "sleeve portion having the groove" function as the "wheel slip-off preventing portion". Therefore, according to the structure of the present invention, the wheel can be prevented from dropping and/or the parts can be prevented from being damaged during the wheel replacement, and the work efficiency of the wheel replacement can be improved.

In the wheel mounting structure according to one aspect of the present invention, the groove may be formed of a first inclined surface (23d), a second cylindrical outer peripheral surface (23c), and a second inclined surface (23e) that correspond to the first side surface (54b), the inner peripheral surface (54a), and the second side surface (54c) that form the annular protrusion, respectively.

According to this aspect, when all the fastening and connecting members are removed, the second side surface abuts against the second inclined surface in a state where the annular projecting portion is completely dropped into the groove. Thus, the annular protrusion is reliably locked to the groove, and the wheel can be effectively prevented from falling off.

In the wheel mounting structure according to the aspect of the present invention, the fastening member may be a hub bolt.

According to this aspect, when all the hub bolts are removed, the wheel is supported only at the sleeve fitting portion. When the supporting force of the sleeve fitting portion to the wheel is insufficient, the wheel falls down and the annular protrusion is disengaged from the fitting portion and locked in the adjacent groove. In particular, when the hub bolts are all removed, the wheel is supported only at the sleeve portion (wheel slip prevention portion). As a result, the wheel can be prevented from falling off.

In the above description, in order to facilitate understanding of the present invention, names and/or symbols used in the embodiments are given in parentheses for the configuration of the invention corresponding to the embodiments described later. However, the components of the present invention are not limited to the embodiments defined by the above names and/or reference numerals. Other objects, other features and attendant advantages of the present invention will be readily understood from the following description of the embodiments of the present invention with reference to the accompanying drawings.

Drawings

Fig. 1 is a sectional view for explaining a wheel mounting structure according to an embodiment of the present invention.

Fig. 2 is an enlarged cross-sectional view of the sleeve portion and the annular protrusion shown in fig. 1.

Fig. 3 is an enlarged sectional view for explaining the dimensions of each part of the sleeve portion shown in fig. 1.

Fig. 4 is a cross-sectional view for explaining a state in which all of the hub bolts are removed in the wheel mounting structure shown in fig. 1.

Fig. 5 is an enlarged cross-sectional view of the sleeve portion and the annular protrusion shown in fig. 4.

Fig. 6 is a view showing an example of a design study of the wheel slip-off prevention mechanism based on the sleeve portion and the annular protrusion portion shown in fig. 1.

Fig. 7 is a cross-sectional view for explaining a state in which all of the hub nuts are removed in the wheel mounting structure according to another embodiment of the present invention.

Fig. 8 is a sectional view for explaining a wheel mounting structure of a conventional device.

Fig. 9 is a cross-sectional view for explaining a state in which all of the hub nuts are removed in the wheel mounting structure of the conventional apparatus shown in fig. 8.

Fig. 10 is a sectional view of a wheel mounting structure according to another embodiment of the present invention.

Fig. 11 is a sectional view of a wheel mounting structure according to another embodiment of the present invention.

Detailed Description

(Structure)

A wheel mounting structure (hereinafter, also referred to as "present mounting structure") according to an embodiment of the present invention will be described below with reference to the drawings.

< wheel mounting State >

Fig. 1 shows a wheel rolling bearing device 10, a hub 20, a drive shaft 30, a disc rotor 40, a wheel 50, a hub bolt 60, and the like. Fig. 1 is a cross-sectional view taken along a rotation axis 90 of a hub 20 of a wheel rolling bearing device 10 with a wheel 50 attached to the hub 20. In the following description, the outboard side refers to a side toward the outside of the vehicle in the direction of the rotation axis 90 (the right side in fig. 1), and the inboard side refers to a side toward the center of the vehicle in the direction of the rotation axis 90 (the left side in fig. 1).

The rolling bearing device 10 for a wheel includes an inner ring 11, a plurality of rows of

rolling elements

12 and 13, an outer ring 14, and a hub 20. The structure of the rolling bearing device 10 for a wheel is well known and is described in japanese patent application laid-open nos. 2008-56122 and 2008-247274. Which are incorporated by reference in the specification of the present application.

The hub 20 includes a hub shaft portion 21, a flange portion 22, and a sleeve portion 23, and is formed by integrally molding these.

The hub shaft portion 21 is formed with splines (not shown) on its inner peripheral surface 21a, and is spline-coupled to the propeller shaft 30. The hub shaft portion 21 is fastened to the propeller shaft 30 by a propeller shaft fastening nut 31, and is fixed so as to be rotatable integrally with the propeller shaft 30.

The flange portion 22 is a substantially disk-shaped portion extending from the hub axle portion 21 in parallel with a plane perpendicular to the rotation axis 90 of the hub axle portion 21. The flange portion 22 is formed with a circular fixing surface 22a that abuts against the mounting surface 41 of the disc rotor 40. Further, a plurality of bolt holes (screw holes) 25 for fastening the hub bolts 60 are formed in the flange portion 22. Only one of the plurality of bolt holes 25 is shown in fig. 1.

The sleeve portion 23 is a portion having a substantially cylindrical shape, which is provided so as to protrude from the hub shaft portion 21 to the outer side of the flange portion 22 with the rotation axis 90 as the center axis thereof. As described later, the sleeve portion 23 is sleeve-fitted to a hole (central hole 52) formed in the center of the wheel 50.

The disc rotor 40 is a member for braking the vehicle, and is sandwiched between the flange portion 22 and the wheel 50. The disc rotor 40 is formed with a mounting surface 41 that abuts the circular fixing surface 22a of the flange portion 22, an abutment surface 42 that abuts the wheel 50, and a hub mounting hole 43 that inserts the sleeve portion 23 into the center of the disc rotor 40.

The wheel 50 is provided with a hub mounting portion 51, and a center hole (hereinafter, also referred to as "center hole") 52, which is a hole for inserting the sleeve portion 23, is opened at the center thereof. Further, the hub mounting portion 51 has a plurality of bolt holes 53, which are holes for inserting the hub bolts 60, formed around the center hole 52 and on a circle concentric with the center hole 52 at equal intervals.

Further, a hub attachment surface 51a that comes into contact with the contact surface 42 of the disc rotor 40 is formed on the inner side of the hub attachment portion 51, and an annular protrusion 54 is provided on the inner circumferential surface of the center hole 52 so as to protrude from the hub attachment surface 51a side toward the center of the wheel 50. As shown in FIG. 2, inThe annular protrusion 54 has a flat portion 54a formed on the top thereof parallel to the rotation axis 90. The flat portion (hereinafter, also referred to as "inner peripheral surface") 54a has a length (thickness) in the direction of the rotation axis 90 of, for example, 3 mm. The inner peripheral surface 54a of the annular protrusion 54 is tapered from the inner side end toward the inner side. The angle of inclination (angle with a line 91 parallel to the rotation axis 90) of the chamfered portion (hereinafter, also referred to as "first side surface") 54b

For example 45.

The inner peripheral surface 54a of the annular protrusion 54 is tapered from the outboard side end toward the outboard side. The angle of inclination (angle with a line 91 parallel to the rotation axis 90) of the chamfered portion (hereinafter, also referred to as "second side") 53c

For example 65.

The hub bolts 60 are fastened to the plurality of bolt holes 25 formed in the flange portion 22, thereby fixing the disc rotor 40 and the wheel 50 to the hub 20.

< Structure of Sleeve fitting portion >

Next, the structure of the sleeve fitting portion will be described.

As shown in fig. 2, four cylindrical outer peripheral surfaces (hereinafter, also simply referred to as "outer peripheral surfaces") having different diameters are formed on the sleeve portion 23 from the built-in side toward the external side. The outer peripheral surface 23a on the innermost side, i.e., closest to the flange portion 22, is a mounting surface for the disc rotor 40, and is also referred to as "disc rotor mounting outer peripheral surface 23 a".

The disk rotor mounting outer peripheral surface 23a abuts against an inner peripheral surface 43a of a hub mounting hole 43 opened in the center of the disk rotor 40. The diameter D0 of the portion where the disc rotor mounting outer peripheral surface 23a is formed is, for example, 68.6 mm.

The second outer peripheral surface from the built-in side is referred to as a first cylindrical outer peripheral surface 23b, the third outer peripheral surface from the built-in side is referred to as a second cylindrical outer peripheral surface 23c, and the fourth outer peripheral surface from the built-in side is referred to as a third cylindrical outer peripheral surface 23 f.

The first cylindrical outer peripheral surface 23b abuts against the inner peripheral surface 54a of the annular protrusion 54. That is, the first cylindrical outer peripheral surface 23b and the inner peripheral surface 54a are sleeve-fitted. The length L1 of the first cylindrical outer peripheral surface 23b in the direction of the rotation axis 90 is, for example, 4 mm. As described above, the length LP of the inner peripheral surface 54a in the direction of the rotation axis 90 is, for example, 3 mm. As can be seen from fig. 2, the length L1 of the first cylindrical outer peripheral surface 23b in the direction of the rotation axis 90 completely covers the length LP of the inner peripheral surface 54a in the direction of the rotation axis 90. Therefore, the length of the contact portion between the first cylindrical outer peripheral surface 23b and the inner peripheral surface 54a in the direction of the rotation axis 90 (hereinafter, also referred to as "contact portion length") is 3mm, which is the same as the length LP of the inner peripheral surface 54a in the direction of the rotation axis 90. The longer the length of the contact portion is, the more stably the wheel 50 is held, but on the other hand, when corrosion occurs on the surface of the hub 20 and/or the wheel 50, the hub 20 and the wheel 50 are easily fixed. In view of the above-mentioned holding stability and easiness of detachment, the length of the abutting portion is preferably 2mm to 3 mm.

The diameter D1 of the portion where the first cylindrical outer peripheral surface 23b is formed (hereinafter also referred to as "fitting portion 24") is smaller than the diameter D0 of the portion where the disc rotor attachment outer peripheral surface 23a is formed, and is 66.5mm, for example. Therefore, the diameter of the inner peripheral surface 54a of the annular protrusion 54 that is sleeve-fitted to the first cylindrical outer peripheral surface 23b is also substantially 66.5 mm. Therefore, the wheel 50 is not fitted into the disc rotor mounting outer peripheral surface 23 a. Thus, even if the disc rotor 40 is forgotten to be mounted, the wheel 50 can be prevented from being erroneously inserted into the disc rotor mounting outer peripheral surface 23 a.

The diameter D2 of the portion where the second cylindrical outer peripheral surface 23c is formed is set smaller than the diameter D1 of the fitting portion 24. As shown in fig. 3, the length L2 of the second cylindrical outer peripheral surface 23c in the direction of the rotation axis 90 is set to be equal to or greater than the length LP of the inner peripheral surface 54a of the annular protrusion 54 in the direction of the rotation axis 90. In the present embodiment, the length L2 of the second cylindrical outer peripheral surface 23c in the direction of the rotation axis 90 is, for example, 3mm equal to the length LP of the inner peripheral surface 54a in the direction of the rotation axis 90.

Connecting the first cylindrical outer peripheral surface 23b and the second cylindrical outer peripheral surface 23cThe angle θ 1 formed by the first slope 23d of (a) and a line 92 parallel to the rotation axis 90 (hereinafter, also referred to as "first inclination angle") is set to 45 °. In this example, the first inclination angle θ 1 and the inclination angle of the first side surface 54b of the annular protrusion 54

(e.g., 45 °) are equal. However, from the viewpoint of improving workability when the wheel 50 is mounted, it is preferable to reduce the first inclination angle θ 1 to facilitate the wheel press-fitting. On the other hand, from the viewpoint of ease of molding (manufacturing cost) of the hub 20, it is preferable to increase the first inclination angle θ 1 and shorten the entire length of the sleeve portion 23.

The diameter D3 of the portion where the third cylindrical outer peripheral surface 23f is formed is set to be larger than the diameter D2 of the portion where the second cylindrical outer peripheral surface 23c is formed, and is equal to or smaller than the diameter D1 of the first cylindrical outer peripheral surface 23b of the portion where the fitting portion 24 is formed. The diameter D3 of the portion where the third cylinder outer peripheral surface 23f is formed is, for example, 65.5 mm. The length L3 of the third cylinder outer peripheral surface 23f in the rotation axis 90 direction is set in consideration of the following points. From the viewpoint of ease of molding of the sleeve portion 23, in other words, production cost, it is preferable that the length Lt in the direction of the rotation axis 90 from the first cylindrical outer peripheral surface 23b to the third cylindrical outer peripheral surface 23f is short. Therefore, the length L3 of the third cylinder outer peripheral surface 23f in the direction of the rotation axis 90 is preferably shortened to a limit at which sufficient strength can be ensured. In this example, the length L3 of the third cylinder outer peripheral surface 23f in the direction of the rotation axis 90 is set to, for example, 2.5 mm.

As will be described later in detail, an angle (hereinafter, also referred to as "second inclination angle") θ 2 formed by the second inclined surface 23e connecting the second cylindrical outer peripheral surface 23c and the third cylindrical outer peripheral surface 23f and a line 92 parallel to the rotation axis 90 is set in consideration of a requirement for the performance of preventing the dropping of the wheel 50. The second inclination angle θ 2 is preferably set to the inclination angle of the second side surface 54c of the annular protrusion 54

(e.g., 65 °) or less. In addition, regarding the above-mentioned respective dimensions (length)Degrees L1-L3, LP and Lt, length of contact portion, diameters D0-D3, and diameter of inner peripheral surface 54a), and angle (inclination angle)

And

the values of the first inclination angle θ 1 and the second inclination angle θ 2), etc. are merely examples to facilitate understanding of the present invention, and do not limit the present invention. These numerical values may be appropriately changed within the scope of the present invention.

(action)

Next, the operation of the embodiment of the present invention will be described with reference to fig. 4 showing a state where the hub bolts 60 are removed.

< hub bolt removal State >

When all the hub bolts 60 are removed, as shown in fig. 4, the wheel 50 is tilted by the weight of the wheel 50 and a tire (not shown) attached to the wheel 50 (hereinafter, also referred to as a "wheel assembly"), and the contact surface (hub attachment surface) 51a of the wheel 50 with the disc rotor 40 is separated from the disc rotor 40, so that the annular protrusion 54 is fitted into the groove 23g formed by the second cylindrical outer peripheral surface 23c, the first inclined surface 23d, and the second inclined surface 23 e.

More specifically, the wheel 50 of the present embodiment is a wheel with a so-called inner offset (positive offset). Therefore, as shown in fig. 1, the center of gravity Gtyre of the tire is located on the inner side of the contact surface (hub attachment surface) 51a of the wheel 50 with the disc rotor 40. Further, the center of gravity Gassy of the wheel assembly is also located on the inboard side of the hub attachment surface 51 a.

Therefore, when all the hub bolts 60 are removed, as shown in fig. 5, a moment is generated with the point P1 as a fulcrum, and the wheel 50 falls. The point P1 slides on the abutment surface 42 of the disc rotor 40 towards the rotation axis 90. The annular protrusion 54 slides to the outer side on the first cylindrical outer peripheral surface 23b, slides down the first inclined surface 23d, the second side surface 54c of the annular protrusion 54 abuts against the second inclined surface 23e at the point P2, and the annular protrusion 54 is locked in the groove 23 g. At this time, the annular protrusion 54 completely falls into the groove 23 g. That is, at the point P2, the wheel 50 is supported by the sleeve portion 23, preventing the drop-out of the wheel 50 (i.e., the wheel assembly). Thus, the "annular protrusion 54" and the "sleeve portion 23 having the groove 23g formed therein" constitute a wheel slip-off prevention mechanism.

< wheel slip prevention mechanism >

Next, as shown in fig. 5, the reaction force acting on the point P1 and the point P2 when all the hub bolts 60 are removed will be described. A component F1 in the direction of the rotation axis 90 (a component toward the inboard side) of the reaction force generated when the wheel 50 acts on the disc rotor 40 at the point P1 is balanced with a component F2 in the direction of the rotation axis 90 (a component toward the outboard side) of the reaction force generated when the wheel 50 acts on the sleeve portion 23 at the point P2.

At the abutting portion between the second side surface 54c of the annular projection 54 and the second inclined surface 23e of the sleeve portion 23, that is, at the point P2, the annular projection 54 and the sleeve portion 23 are engaged with each other. However, if the reaction force F2 is larger than the component (component toward the inner side) F3 of the force generated by the engagement in the direction of the rotation axis 90, the annular protrusion 54 slides on the third cylindrical outer circumferential surface 23F toward the outer side beyond the second inclined surface 23e, and finally falls off from the sleeve portion 23.

More specifically, the force F3 generated by engagement at the point P2 is a component of the vertical resisting force FN acting on the second inclined surface 23e in the direction of the rotation axis 90. Hereinafter, the force F3 generated by the engagement is also referred to as a resisting force F3. The resisting force F3 is mainly determined by the weight of the wheel assembly and the inclination angle θ 2 of the second inclined surface 23 e. Fig. 6 is a graph having the weight of the wheel assembly as the horizontal axis and the reaction force F2 and the resistance force F3 as the vertical axis. Force F3 is proportional to the wheel assembly weight. The larger the inclination angle θ 2 of the second slope 23e, the larger the resistance F3. On the other hand, the reaction force F2 is mainly determined by the weight of the wheel assembly and the position of the center of gravity of the wheel assembly. Therefore, the reaction force F2 was estimated with respect to about 70 representative wheel assemblies that differ in the weight of the wheel assembly, the offset amount of the wheel, the rim width of the wheel, and the material of the wheel (aluminum wheel or steel wheel). As a result, a straight line (line indicating the resistance F3) was obtained under the condition that all points plotted in the graph of fig. 6 were 50 ° lower than the second inclination angle θ 2. That is, this result indicates that if the second inclination angle θ 2 is set to 50 °, all the wheel assemblies do not fall off the sleeve portions 23. From the above results, in the present embodiment, the second inclination angle θ 2 is set to 60 ° larger than 50 °.

Of course, the present invention is not limited to such a value, but it is preferable that the second inclination angle θ 2 is set to 50 ° or more and is an inclination angle of the second side surface 54c of the annular protrusion 54

(e.g., 65 °) or less.

< example of fastening connection by hub nut >

Next, an example of fixing the wheel by fastening with the hub nut will be described. Fig. 7 shows a state in which a serration bolt 600 is provided so as to protrude outward in place of the bolt hole 25 formed in the flange portion 22, and the hub nut, not shown, is completely removed. When the hub nut is removed, as shown in fig. 7, the wheel 50 is tilted by the weight of the wheel assembly, and the contact surface (hub attachment surface) 51a of the wheel 50 with the disc rotor 40 is separated from the contact surface 42 of the disc rotor 40, and the annular protrusion 54 is fitted into (locked to) the groove 23g formed by the second cylindrical outer peripheral surface 23c, the first inclined surface 23d, and the second inclined surface 23e, as in the case shown in fig. 4.

In this case, since the serration bolt 600 is inserted into the bolt hole 53 of the wheel 50, the wheel 50 is less likely to be detached even if the annular protrusion 54 is not locked to the groove 23 g. However, by engaging the annular protrusion 54 with the groove 23g, the serration bolt 600 can be prevented from being deformed (bent, crushed with the thread, etc.) without applying a large force to the serration bolt 600.

In this way, the present mounting structure can also be applied to a case where the wheel 50 is fixed to the hub 20 by fastening with a hub nut.

< conventional Structure >

In order to compare this mounting structure, a conventional fitting structure for fixing a wheel by fastening a hub nut to a bolt protruding from a hub will be described below with reference to fig. 8.

As shown in fig. 8, serration bolts 600 are press-fitted into bolt holes formed in flange portion 220 of conventional hub 200. The surface 410 of the disc rotor 400 abuts against the abutment surface 220a of the flange portion 220 perpendicular to the rotation axis 90. The hub attachment surface 510a abuts against the surface of the disc rotor 400 opposite to the surface 410 to fix the wheel 500.

In order to facilitate the alignment of the center position of the wheel 500 with the rotational axis 90 of the hub 200, a center hole 520 formed in the center of the wheel 500 is fitted over the annular protrusion 230 provided on the hub 200. That is, the inner peripheral surface 540a of the annular protrusion 540 protruding from the inner peripheral surface of the center hole 520 is in surface contact with the outer peripheral surface 230b of the protrusion 230, but the surface contact portion (the overlapping portion of the inner peripheral surface 540a and the outer peripheral surface 230 b) is formed near the tip of the protrusion 230 in the rotation axis 90 direction, and the length Lu of the surface contact portion in the rotation axis 90 direction is made short. In this example, the length Lu is set to about 3 mm. With such a fitting structure, even when the protrusion 230 and/or the wheel 500 are corroded and fixed, the wheel 500 can be relatively easily removed (with a small force). The wheel 500 is fixed to the hub 200 by tightening the hub nuts 700 with the respective serration bolts 600 connected to the plurality of bolt holes 530 penetrating the wheel 500.

When the wheel 500 attached to the hub 200 is removed, all the hub nuts 700 are removed from the serration bolts 600, but if the sleeve fitting portions are not fixed, moment may be generated depending on the position of the center of gravity of the wheel assembly, and the annular protrusion 540 of the center hole 520 of the wheel 500 may be detached from the protrusion 230. Even in this case, as shown in fig. 9, since the bolt hole 530 of the wheel 500 is supported by the serration bolt 600, the wheel assembly can be prevented from falling off. However, since a large force is applied to the serration bolt 600, there is a problem in that the serration bolt 600 may be deformed.

As described above, according to the present mounting structure, the hub 20 includes: a hub shaft portion 21; a flange portion 22 that is a disk-shaped portion extending from the hub axle portion 21 in parallel with a plane perpendicular to the rotation axis 90 of the hub, and that has a fixing surface 22a for fixing the wheel 50 using a plurality of fastening connection members 60 on the vehicle body outer side (outboard side); and a sleeve portion 23 which is a cylindrical portion having a rotation axis 90 as a central axis and which protrudes from the hub shaft portion 21 to a position outside (outboard side) the flange portion 22, a center hole 52 through which the sleeve portion 23 can be inserted is formed in the center of the wheel 50, a plurality of bolt holes 53 through which a plurality of fastening members 60 can be inserted are formed around the center hole 52, a first cylindrical outer peripheral surface 23b having the rotation axis 90 as a central axis and a groove 23g adjacent to the first cylindrical outer peripheral surface 23b on the vehicle body outer side (outboard side) of the first cylindrical outer peripheral surface 23b are formed in the sleeve portion 23, an annular protrusion 54 protruding toward the center of the wheel 50 is formed on a hub attachment surface 51a side of the wheel 50 on an inner peripheral surface of the center hole 52, and the wheel 50 is fixed to the flange portion 22 using the plurality of fastening members 60, the fitting portion 24 formed on the first cylindrical outer peripheral surface 23b is sleeve-fitted to the annular protrusion 54, and the annular protrusion 54 is engaged with the groove 23g in a state where the fixation of the wheel 50 using the plurality of fastening members 60 is released.

As described above, in the wheel hub having the structure in which the wheel is fixed by fastening the hub bolts or the hub nuts, the wheel can be prevented from dropping and/or damaging the parts during the wheel replacement, and the work efficiency of the wheel replacement can be improved.

< modification example >

The present invention is not limited to the above-described embodiments, and various modifications can be adopted within the scope of the present invention as described below.

In the above embodiment, the cross-sectional shape of the groove is a substantially trapezoidal shape including the bottom side (the second cylindrical outer peripheral surface 23c) and the two inclined surfaces (the first inclined surface 23d and the second inclined surface 23e) provided on the left and right of the bottom side, respectively, but may be a shape without a bottom surface as shown in fig. 10. Further, the sectional shape of the groove may be a circular shape as shown in fig. 11.

In the above embodiment, the annular protrusion 54 is formed of the inner peripheral surface 54a, the first side surface 54b, and the second side surface 54c, and the cross-sectional shape thereof is trapezoidal, but the inner peripheral surface 54a and the first side surface 54b and the inner peripheral surface 54a and the second side surface 54c may be chamfered at predetermined radii. Similarly, the groove 23g is formed by the second cylindrical outer peripheral surface 23c, the first inclined surface 23d, and the second inclined surface 23e, and has a trapezoidal cross-sectional shape, but the space between the second cylindrical outer peripheral surface 23c and the first inclined surface 23d and the space between the second cylindrical outer peripheral surface 23c and the second inclined surface 23e may be chamfered at predetermined radii.

In the above embodiment, the first side surface 54b and the second side surface 54c of the annular protrusion 54 are flat surfaces, but the first side surface 54b and the second side surface 54c may be curved surfaces. Similarly, the first inclined surface 23d and the second inclined surface 23e of the groove 23g are flat surfaces, but the first inclined surface 23d and the second inclined surface 23e may be curved surfaces.

In the above embodiment, the disc rotor 40 is used, but the form and shape of the brake are not particularly limited to the present invention, and a drum may be used instead of the disc rotor 40.

Description of the reference numerals

10 … rolling bearing device for wheel, 20 … hub, 21 … hub shaft portion, 22 … flange portion, 22a … fixed surface, 23 … sleeve portion, 23b … first cylindrical outer peripheral surface, 23c … second cylindrical outer peripheral surface, 23d … first inclined surface, 23e … second inclined surface, 23f … third cylindrical outer peripheral surface, 24 … embedded portion, 40 … disc rotor, 50 … wheel, 51 … hub mounting portion, 51a … hub mounting surface, 52 … center hole, 53 … bolt hole, 54 … annular protrusion portion, 54a … inner peripheral surface, 54b … first side surface, 54c … second side surface, 60 … hub bolt, 70 … hub nut, 90 … rotation axis.

Claims

1. A wheel mounting structure for mounting a wheel to a hub of a vehicle,

the hub is provided with:

a hub shaft portion;

a flange portion that is a disk-shaped portion extending from the hub shaft portion in parallel with a plane perpendicular to a rotation axis of the hub, and that has a fixing surface for fixing the wheel using a plurality of fastening connection members on an outer side of a vehicle body of the vehicle; and

a sleeve portion that is a cylindrical portion having the rotation axis as a central axis and that protrudes from the hub shaft portion to the vehicle body outer side of the flange portion,

a center hole through which the sleeve portion can be inserted is formed in the center of the wheel, and a plurality of bolt holes through which the plurality of fastening and connecting members can be inserted are formed around the center hole,

the sleeve portion is formed with a first cylindrical outer peripheral surface having the rotation axis as a central axis and a groove adjacent to the first cylindrical outer peripheral surface on the vehicle body outer side of the first cylindrical outer peripheral surface,

an annular protrusion protruding toward the center of the wheel is formed on the hub attachment surface side of the wheel on the inner peripheral surface of the center hole,

a fitting portion formed on the outer peripheral surface of the first cylinder is sleeve-fitted to the annular protrusion portion in a state where the wheel is fixed to the flange portion using the plurality of fastening members,

the annular protrusion is locked in the groove in a state where the fixation of the wheel using the plurality of fastening and connecting members is released.

2. The wheel mounting construction according to claim 1,

the groove is formed by a first inclined surface, a second cylindrical outer peripheral surface, and a second inclined surface, which correspond to the first side surface, the inner peripheral surface, and the second side surface, respectively, which form the annular projecting portion.

3. The wheel mounting construction according to claim 1 or 2,

the fastening and connecting part is a hub bolt.